AccessControlException

I have (what i believe is) my server coded. In a nutshell I have my interface with the needed client methods from the data class and implemented them in my server class.
When I try to creat a new server object i get the following runtime error:
Problem with server: java.security.AccessControlException: access denied (java.io.FilePermission db.db write)
java.security.AccessControlException: access denied (java.io.FilePermission db.db write)
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:272)
at java.security.AccessController.checkPermission(AccessController.java:399)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:545)
at java.lang.SecurityManager.checkWrite(SecurityManager.java:978)
at java.io.File.canWrite(File.java:516)
at suncertify.db.Data.<init>(Data.java:40)
at suncertify.db.RMIServer.<init>(RMIServer.java:25)
at suncertify.db.RMIServer.main(RMIServer.java:114)
Any light shed on this on this would be immensley appreciated.
Dave

With LOTS of tinkering I finally created my server object. I'm now stuck on this error:
Problem with server: java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: suncertify.db.RMIServer_Stub
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: suncertify.db.RMIServer_Stub
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: suncertify.db.RMIServer_Stub
java.lang.ClassNotFoundException: suncertify.db.RMIServer_Stub
at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:245)
at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:220)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:354)
at sun.rmi.registry.RegistryImpl_Stub.rebind(Unknown Source)
at java.rmi.Naming.rebind(Naming.java:160)
at suncertify.db.RMIServer.main(RMIServer.java:116)
Dave